Pattern of yolk internalization by hatchlings is related to breeding timing in the garden lizard, Calotes versicolor

Abstract

Pattern of yolk internalization by hatchlings born in early (May-June), mid (July-August) and late (September- October) breeding season in relation to maternal, egg and hatchling sizes was studied in Calotes versicolor. The maternal snout-vent length (SVL), body mass, clutch size, clutch mass and egg mass were recorded. Eggs from five clutches each, from early, mid and late breeding periods were incubated at ambient room temperature until hatching. At hatching, SVL and body mass of the hatchlings, and amount of yolk internalized by hatchlings were recorded. The internalized yolk mass of hatchlings was not related to maternal SVL, body mass, clutch mass and hatchling SVL. Internalized yolk mass was positively correlated with egg mass and hatchling body mass. Significantly greater amount of yolk was internalized by hatchlings born in the later part of the breeding season. Production of heavier hatchlings with greater amount of internalized yolk appears to be an important strategy to enhance the fitness of hatchlings of later clutches that have to compete for food with conspecific hatchlings of earlier clutches.